A judge has stopped a major case against a Nelson gang after the police seriously abused the court process.
The case involves a covert investigation into the Red Devils Motorcycle Club, in which police faked the arrest of a planted undercover officer and had the agent prosecuted through the courts.
The false prosecution came to light after 21 people netted in the sting were charged with a variety of offences, including participating in an organised criminal group.
The undercover officer had infiltrated the gang but they were suspicious of him, so in May 2010 police set up a fake drug bust using a fake search warrant to arrest him.
Police told the Chief District Court judge some details about the operation, but the information was never passed to the presiding judge or the undercover agent's lawyer, who both treated it like any other case before the courts.
In a High Court ruling on Wednesday, Justice France said police seriously abused the court process, lacked insight and were reckless.
The judge said fake search warrants appearing to come from a judicial officer were used and false charges involving the swearing of a false oath were issued, as well as further opportunistic abuse of the court processes.
Justice France said that while police did not intend to mislead the court, the ruse reflects a serious misunderstanding of the role of the court and its independence.
All prosecutions of the 21 accused have been stayed and the judge suggested that elements of criminal offences may have been committed by the police, but added it is up to other authorities to decide if charges should be laid.
Steven Rollo, a lawyer representing the gang members, said his clients do not pose a risk to the public and the lengths police went to were not justified.
"The allegations that they faced were nowhere near at the serious end of the scale. I don't think that the people of Nelson have anything to worry about these people, bearing in mind they've lived happily in Nelson - many of them all of their lives - without incident."
Lawyer 'doesn't feel duped'
The lawyer who represented the undercover officer prosecuted says he does not feel duped by police.
Tony Bamford told Radio New Zealand's Checkpoint programme on Wednesday it does not bother him that he did not know that his client was undercover.
"I understand now having looked at the background what the police were doing. I think they made some bad calls and the judge has commented on that.
"So I suppose from my end, no, I don't feel duped. You deal all sorts of with different people when you're a defence lawyer. You take people as you find them and you don't necessarily assume that everything or anything they say is actually correct."
Mr Bamford lives in Nelson and said he does not feel threatened by the Red Devils.
Call for independent inquiry
The president of the Criminal Bar Association says there should be an independent inquiry to establish whether police should face charges for undermining the court process during the undercover operation.
Auckland barrister Tony Bouchier worked as an undercover officer in the 1970s and says the public has a right to know that the police have not abused the justice system.
Mr Bouchier told Checkpoint that the fake prosecution was approved at the highest echelons of the police force.
"I think that there has has got to be an independent inquiry. I cannot think of any case at all where the police should be entitled to embark on false search warrants which require affidavits on oath, the laying of charges which require a constable to swear on oath that he has good cause to suspect that the charge has been committed at all."
Police Minister Anne Tolley said on Wednesday she has confidence in the force and believes the case has to be put in perspective, as officers are dealing with thousands of cases at a time.
However, Mrs Tolley said it is disappointing to see gang members not brought to justice for crimes as serious as firearms and drug dealing.